Inner Core Composition

Why is the inner core important?

The solid inner core is complex and not yet fully understood. This is hardly surprising given that the temperature of the Earth's core (q.v.) is in the range 5000–6000 K and inner core pressures are ∼330–360 GPa. Knowledge of the exact composition and structure of the Earth's inner core would enable a better understanding of the internal structure and dynamics of the Earth as a whole; in particular, better constraints on core composition (q.v.) would not only have fundamental implications for models of the formation, differentiation, and evolution of the Earth, but would also enable successful interpretation of seismic observations which have revealed inner core anisotropy (q.v.), layering and heterogeneity (e.g., Creager, 1992; Song, 1997; Beghein and Trampert, 2003; Cao and Romanowicz, 2004; Koper et al., 2004). The elastic anisotropy of the inner core is well established: seismic velocities of the inner core ...